change

getNextSequence

The next element sequence value for this proxy at load time.
If the data store keeps this proxy's data in sequence order but allows
holes for removed objects, the implementation can set the next
sequence at load time, then retrieve it and start from there for
added objects at flush time. This value is set back to 0 if the
proxy stops tracking changes. For ordered proxies, it is set to the
proxy's size when the proxy starts tracking changes again.

setNextSequence

The maximum element sequence value for this proxy at load time.
If the data store keeps this proxy's data in sequence order but allows
holes for removed objects, the implementation can set the next
sequence at load time, then retrieve it and start from there for
added objects at flush time. This value is set back to 0 if the
proxy stops tracking changes. For ordered proxies, it is set to the
proxy's size when the proxy starts tracking changes again.